Various subsurface infrastructure such as power cables, water lines, gas lines, and product piping may be installed by drilling operations. Horizontal directional drilling is a trenchless drilling technique often used in urban areas and for crossing below roads or waterways. Drilling involves formation of a pilot hole along the drill path. The pilot hole is then reamed out to the size of the utility. During drilling, a viscous drilling fluid that typically contains bentonite or polymer is pumped to the cutting head. The drilling fluid, for example, cools the cutting head and carries drill cuttings away from the drill bore. Spent drilling fluid may be collected by use of vacuum excavators. Such vacuum excavators may also collect fluid from vertical well drilling.
Vacuum excavators are also used in a process commonly referred to as “potholing”, “daylighting” or “locating.” Potholing involves use of high pressure water that loosens soil to create a hole to visually locate utilities. The mud slurry that is produced is removed by a vacuum and sent to a spoil tank. High pressure systems may also be used to cut trenches with the resulting slurry being sent to a spoil tank of a vacuum excavator. Vacuum excavators may also be used to remove water/mud slurries from valve and meter boxes to provide access to the boxes.
The raw slurry produced during drilling or potholing, typically collected by vacuum excavators, is conventionally landfilled or dumped at a designated disposal site. Landfill disposal of slurries containing a large amount of water may be relatively expensive compared to disposal of solids alone. Further, tightening regulations may limit disposal options for such slurries.
A need exists for dewatering systems and methods for processing earthen slurries such as drill cuttings and cuttings from potholing. A need exists for systems and methods that allow slurries to be dumped with ease and that allow for multiple loads to be dumped while processing slurries. A need also exists for systems and methods that allow the cuttings to be processed without blinding and with reduced wear during the dewatering process.
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.